The purpose of this contract is to develop improved methodologies to assess diabetic neuropathy, with particular emphasis upon peripheral autonomic function. Specific objectives are: 1.1 Development of methods to quantitate postganglionic sympathetic sudomotor denervation in diabetic neuropathy. 1.2 Evaluation of the use of the venoarteriolar reflex in defining postganglionic sympathetic vasomotor denervation of human skin in diabetic neuropathy. 1.3. Evaluation of a miniaturized laser doppler probe to define the proximodistal distribution of denervation of the muscle resistance bed. 1.4 Development of methods to define the distribution of postganglionic vasomotor denervation and dysfunction in diabetic neuropathy.